Cleaning device for submersible burners



Nov. 14, 1950 N; SWINDIN 2,530,270

CLEANING DEVICE FOR SUBMERSIBLE BURNERS Filed Feb. 4, 194 4 Sheets-Sheet1 MN MM; N #TMTW Ali-0r!) nus Npv. 14, 1950 N. SWINDIN 2,530,270

CLEANING DEVICE FOR SUBMERSIBLE BURNERS Filed Feb. 4} 1946 '4Sheets-Sheet 2 5 mu /tar 1 E y a I I Nov. 14, 1950 N. SWINDIN 2,530,270

CLEANING DEVICE FOR SUBMERSIBLE BURNERS Filed Feb. 4, 1946 4Sheets-Sheet 3 Attorneys Nov. 14, 1950 N. swmnm 2,530,270

CLEANING DEVICE FOR SUBMERSIBLE BURNERS Filed Feb. 4, 1946 4Sheets-Sheet 4 /n V8060! 15y M M u% 4 Attorney:

Patented Nov. 14,1950

I CLEANING DEVICE FOR SUBMERSIBLE BURNERS Norman Swindin, London,England Application February 4, 1946, Serial No. 645,392 In GreatBritain September 18, 1944 1 -This invention relates to improvements inconnection with submersible burners and has more particular referencebut without limitation to such burners as are employed for raising thetemperature of acid reagents such as are employed in steel picklingprocesses and. of solution concentratorsand the like.

In such applications the flame orifices of the burners tend to encrustwith precipitated salts due to excessive evaporation of solvent at oradjacent to the orifice, and this precipitation tends to build until theorifice is closed and the burner ceases to function or even backfires.

The object of the present invention is to clear such deposits eitherautomatically as occasion requires or according to a present timecontrol for repeated operation whilst the burner is at work, andembraces, the employment of a pricker whose action is to clear the jetorifice of obstruction.

It has been ascertained that submerged burner nozzles can be effectivelcleared if the application of the pricker be sudden, or quickly re- 11Claims. (01. 158-120) peated with a time interval between eachmultioperation group of cleaning operations. Furthermore the'to'ol orscraper employed must be such as to effect the required salt detachmentwithout quenching the submerged flame.

The invention consists in an improved pricking, device for cleansing theflame orifices of submerged flame burners, and means for operating samecomprising in combination, a cleansing tool positioned when inoperativeaway from said burner, means for reciprocating said pricking devicetowards and into said flame orifice and means for producing operativereciprocation automatically either under time control or dependent uponthe performance of' the burner and after operation means for returningsaid pricker to its starting position.

The'means for automatic operation of the:

reciprocating mechanism may embrace devices sensitive to fluid flowwhereby variation in the rate of gas fed to the burner determinestheinstant of pricker operation, or the reciprocating mechanism maybeunder time control of an electrical and mechanical nature.

The cutting head of the pricking device must.

offer the smallest possible resistance to the. gases issuing from theburner and a preferred form of the invention consists of a chisel-edgedtube adapted to engage the interior-Walls of the burner nozzle and cutaway any incrustation.

In order that the invention shall be better understood, reference ismade to the accompanying drawings wherein:

Fig. 1 is a diagrammatic illustration of the invention in part sectionalelevation showing means for automatic operation of the pricker devicedependent upon the state of incrustation of the burner; p i

Fig; 2 shows in like'manner to Fig. 1 a modified form of the meansforautomatic operation, Fig. 3 shows a further modification, and

Fig. 4-shows diagrammaticall means for op erating thepricker deviceunder time control.

Referring to the drawing and to Fig. 1, the

submerged fiameburner- I is of a known type mounted in an enclosedcontainer 2 which is' sensitive to gas flow to the burner jet. A staticmercury switch 6 of the reservoir and rising tube:-

type is disposed adjacent the orifice plate 5, and conduits 1 and 8 areled respectively the one I to the mercury reservoir 9 and conduit 8 tothe rising tube [0. The rising tube ID has electrical contacts llpassing through a sealed joint con? trolling the supply circuit [2 forelectrical energy to a solenoid switch I3.

The solenoid switch 13 is adapted to open or close an energising circuitto a static plunger solenoid [4, whose core extension rod l5 linked tothe extremity of rocker arm l6, said arm being pivoted at IT, andcarrying at itsotherextremity a connecting rod [8 hinged to a com' poundpiston valve 19 operating in the valve cylinder 20 of a valve box 2|, ofa fluid motor in main cylinder 24. Theexhaust ports 22a have an exit inpart common to theinletportsl adjacent the working cylinder. Hence,upon: movement of the compound piston valve under movement of the rockerarm l6 energisingfiuid is admitted to the workingcylinder 24 to raise orlower the piston 23. Due to the positive stroke of the solenoid rod [5the throw of the arm I6 compels the piston valve H] to occupy one. oftwo definite positions, i. e. it operateseither to raise the piston orlower it. The piston'23 is fitted with a piston rod 25 passing throughguide 26, said piston rod entering an aperture 21 in the submergedburner tank 2 and an arm 28 at right angles to the piston rod 25carriesthepricking tool 29. This latter consists of a heat Gas supplytothe burn resisting alloy steel tube having chisel edges to cut, orsquared-01f edges to shear away incrustation formed within the burnerbody I. Due to the fact that the burner container 2 is under pressurethe piston rod 25 enters therein under a rubber or like sealing bellowsas shown at 30. The said piston rod 25 also carries a trip arm 3|adapted to tilt the tail 32 of a pivoted time delay mercury switch 33,said switch 33 being adapted to break the circuit l2 to the solenoidswitch I3 when the trip 3! tilts the tail 32 of the pivoted switch.

The operation of this form of the invention is as follows: According tothe drawing, the prick ing device 29 is at rest and the burner operatingnormally, the mercury level in I being depressed by the difierence ofpressure created by flow through the orifice plate 5, and the electricalcircuit [2 open. The pricker is held at position shown by piston 23which is subject to pressure. Should, however, the burner body getchoked with incrustation the outlet for the flame decreases and lessgasand air pass through the orifice plate 5 in gas conduit 4. This reducesthe difierenceof pressure and mercury is displaced up the tube l0closing contacts to the electrical circuit !2. This energises solenoidswitch 43 closing main; supply circuit to the plunger solenoid 14 whichraises the arm l6 of rocker lever and thereby moves the-piston valvedownward admitting fluid to the underside of working piston 23 andraising same, exhaust of spent fluid issuing from exhaust port 22a onthe upper side. Raising of the piston 23 equally raises the pricker 29and inserts same within the burner body I. Incrustation removed fallsthrough the hollow interior of the pricker and the burner is cleared ofobstruction. Assuming the pricker 29 to be at the end of its upwardstroke, it must be returned to its.

will remain closed, and operation of pricking will continue at thepre-determined interval of the time delay switch until the burner isclear of obstruction. The piston rod passing through the guide 26' maybe rectangular in section to preservealignment of the pricker head 29with the burner i. be inserted about the entry point of the piston Afurther perforate guide nut 40 may.

rod 25 to the burner chamber 2 or at any other convenienttpoint, and thesaid rectangular section piston rod be articulated-at M, and-pros videdwith a slight twist 4m; which, on entry through a counterpart thread innut 40, will impart a sufficient degree of rotation to the-lower.

portion of the rod 25 and angularity to the pricker to clear the pricker29 from the flame path of the burner. The amount of rotation maybe onlyof the order of say degrees.

In Fig. 2 the arrangement is somewhat simplified'in that the secondsolenoid I4 is employed to operate the pricker rod, the core plunger [5protruding above the solenoid body and used to operate the time-delayswitch 32.

In Fig; 3 the solenoid I4 is replaced by a motor 43 adapted to energiseaknown type of thruster apparatus 44 wherein a horizontal centrifugalpumpdelivers fluid to a iston under pressurew of strokes of the prickertoolto'clear away ings.

which raises the thruster piston rod 45 to operate the arcuately movinglever 46 pivoted at 41 and raises the pricker rod. In this device themoment the time-delay switch 32 opens the solenoid switch circuit [2 thepump ceases to feed the fluid to the piston when the weight of the partsattached to the lever 46, and with the assistance of the spring 48 thepiston drives the fluid through the pump vanes and finally occupies azero position of rest as shown in the draw- The operation otherwise isas described under Fig. l.

In Fig. 4 the pricking device is shown as actuated by a pre-set timingdevice wherein a single phase electrical synchronously drivenself-starting motor 50 is geared according to requirement to a rotarycontact disc 51 wherein the stop and start contacts of two push buttontype of motor switch starters 52 and 53 are wired to the contact brushes54, a common return circuit brush 55 completing the circuit. Under thisarrangement time control current is fed to geared motor 56 to whoseshaft 51 a crank 58 is fitted driving the pricker rod. The shaft 51 hasa pinion 59 meshing with wheel 60, said wheel 60 carrying a trip pin 6|,operating once per revolution the mercury switch 32. The leads 66 aretaken to the brake 63.

Thus the synchronous motor constitutes the time piece and the time ofdwell of the contacts on the circuit determines the duration of currentsupply to the pricker driving motor 56. The latter causes the prickerrod to reciprocate and the interrupter wheel 60 trips by pin BI and bellcrank lever 6la the switch 32 as previously described, interrupting thecircuit to the motor 56. To ensure that the pricker 29 comes to rest inits zero position, and apart from accurate adjustment of the parts aperipheral electrical brake 63 comes into operation to engage a brakedrum 64 mounted on the spindle of motor 56. The electromagnets of thisbrake are wired to the stop mechanism of the switch device 52.

By the above mentioned devices submerged flame burners can be maintainedin a high state of efficiency during their operation, and what isequally important, blow outs, back fires and the time lost in cleaningthe burner bodies or flame orifices is obviated.

I claim: r

1. An improved pricking device for cleansing the flame orifice of asubmerged flame burner,.

having in combination an electrical synchronous self-starting motor, acontact disc geared thereto, a power circuit switching device controlledby i said contact discand a motor, adapted to be en ergised by saidpower switching device, said motor driving a reciprocating pricker rodupwardly and downwardly through the flame orifice of the burner andtripping means geared to said motor for interrupting current to thepower switching device and motor.

2. An improved pricking device for cleansing the flame orifice of asubmerged flame burner as defined in claim 1, including an electricallycontrolled brakin device operative to arrest the driving motor momentumwhen the burner pricking rod is at its lowermost position.

3. An improved'pricking device for cleansing the flame orifice of asubmerged flame burner, comprising a pricker tool reciprocable towardand away from the flame orifice of the burner," and means controlled bythe flow of gaseous fuel to the'burner for producing either one or aseries assay/o crustation of the flame orifice according to the needtherefor and as determined by the burner itself, the pricker tool beingtubular for the passage of the flame therethrough during cleansing ofthe flame orifice.

4. A pricking device for cleansin the flame orifice of a submerged flameburner mounted in a chamber containing liquid to be concentratedcomprising, in combination, a pricking tool mounted in said chamber forimmersion in liquid therein and for upward and downward movement towardand into an inoperative position below and away from the flame orificeof the burner, means for reciprocating the pricking tool upwardly towardand into the flame orifice, and controlling means for said reciprocatingmeans for automatically producing operative reciprocation of thepricking tool and for subsequently returning the pricking tool to itslower inoperative starting position below and away from the flameorifice of the burner.

5. A pricking device for cleansing the flame orifice of a submergedflame burner mounted in a chamber containing liquid to be concentratedcomprising, in combinaton, a pricking tool mounted in said chamber forimmersion in the liquid therein and for upward and downward movementtoward and into an inoperative position below and away from the flameorifice of the burner, means for reciprocating the pricking toolupwardly toward and into the flame orifice and for lowering it to apositon below said orifice, and controlling means for said reciprocatingmeans for automatically producing operative reciprocation of thepricking tool, the latter com- 2:.

prising a tubular member having a cutting or shearing edge reciprocableaxially into the flame orifice without obstructing the passage of theflame through the flame orifice.

6. A pricking device as defined in claim 4, wherein said controllingmeans is controlled by the flow of gaseous fuel mixture to the burner.

7. A pricking device for cleansing the flame orifice of a submergedburner comprising, in

combination, a pricking tool movable toward and into an inoperativeposition away from the flame orifice, power means for reciprocating thepricking tool, a gas conduit to the submerged flame burner, an orificeplate disposed in said conduit, a primary power switching device forcontrolling said power means, a mercury switching device operating toopen or close the primary power switching device in response todiflerential pressure on opposed sides of said orifice plate, a solenoidcontrolled by said primary power switching device and controlling theoperation of the means for reciprocating the pricking tool,

and tripping means operative at the limit of travel of the pricking too1toward the flame orifice to open the power switching device and therebycause return of the pricking device to its inoperative position.

8. A pricking device as defined in claim 7, wherein said power meanscomprises a fluid pressure operated piston connected to the prickingtool and a valve controlling it, said valve being operative at thetermination of any operation of the pricking tool to cause the saidpiston to hold the pricking tool away from the flame orifice of theburner.

9. A pricking device for cleansing the flame orifice of a submergedflame burner comprising a pricking tool reciprocable toward and from theflame orifice of the burner, and means operative by reciprocation of thepricking tool for turning the pricking tool sufliciently to remove ittransversely from the path of the burner flame when the prickingoperation is completed and to move it into alignment with the flameorifice of the burner at the commencement of its cleansing operation.

10. A pricking device as defined in claim 9, wherein said pricking toolcomprises an articulated rod, and said turning means comprises a spiralthread out upon the length of said rod, and a correspondingly threadedstatic nut cooperative with said thread.

11. A pricking device for cleansing the flame orifice of a submergedflame burner, comprising a closed chamber enclosing the burner, apricking tool within said chamber reciprocable toward and from the flameorifice of the burner and having an operating rod extending through awall of the chamber to the exterior thereof, and an expansible andcontractable flexible closed bellows having its ends connectedrespectively to the chamber wall and to the pricking tool rod and.providing a fluid tight seal between the chamber and said rod.

NORMAN SWINDIN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 793,894 Mitchell July 4, 19051,327,740 Rossell Jan. 13, 1920 1,605,423 Ballard NOV. 2, 1926.2,342,228 Treat Feb. 22, 1944 2,344,758 Welsh Mar. 21, 1944 2,388,386Cohen Nov. 6, 1945

